Multiple position switch



Aug. l0, 1954 T. J. OBSZARNY MULTIPLE POSITION SWITCH Filed Aug. 9, 1952 Patented Aug. 10, 1954 MULTIPLE POSITION SWITCH Thedore J. Obszarny,

Guardian Electric M Chicago, Ill., assigner to anufacturing Co., Chicago,

Ill., a corporation of Illinois Application August 9, 1952, Serial No. 303,568

Claims. l

This invention relates switches, and more tilting disc type.

Multiple position switches have heretofore been proposed employing a disc tiltable to any one of a plurality of positions selectively to engage different ilxed contacts and establish diiierent circuits. As heretofore constructed, such switches usually include a tiltable contact disc having a circular flat base to fit against a circular flat contact seat and Within a circular peripheral flange on the seat. The opposite face of the disc is engaged by a spring pressed operating plunger in a tiltable handle to tilt the disc as the handle is tilted.

In such constructions the contact between the disc and seat when the disc is tilted is substantially a point Contact. The disc is therefore tiltable to any angular position and is relatively unstable so that it can engage two of the xed contacts simultaneously unless the tilting movements of the handle are carefully restricted. This is very undesirable and may create serious problems in certain types of controls such as aircraft controls. Furthermore, due to the small contact area between the disc and seat the disc tends to heat excessively under high load current conditions.

It is one of the objects of the present invention to provide a. multiple position switch in which the contact disc is guided to tilt only in selected directions and to be stable when tilted in any such direction.

Another object is to provide a switch in which a relatively large contact area is provided between the seat and the disc so that relatively large current can be carried with a minimum of heating.

A further object is to provide a switch in which the seat and disc are dened by a series of connected straight lines registering with the xed contacts to limit tilting of the disc to directions toward the fixed contacts, and to provide a large contact area between the disc and seat.

The above and further objects and advantages of the invention will be more readily apparent from the following description when read in connection with the accompanying drawing, in which Figure l is a side elevation of a. switch embodying the invention.

Figure 2 is a central section on an enlarged scale,

Figure 3 is a horizontal section on the line 3 3 of Figure 2.

Figure 4 is an end view looking from the left of Figure 2, and

to multiple position particularly to a switch of the Figures 5, 6, 7 and 8 are sections on the lines 5 5, 6 6, 1 1, and 8 8, respectively, of Figure 2.

The switch as shown comprises a mounting bracket Hl having a base portion and a fiat end portion Il to receive and support the switch construction. The switch mechanism is enclosed in a cup-shaped housing I2 whose closed end nts against the end il of the mounting bracket and is secured thereto by rivets I3. Preferably a separate plate I4 is mounted between the end of the housing and the end plate H of the bracket.

A tubular handle l5 projects through the end of the bracket and of the housing and is supported for universal angular movement therein. For this purpose, the handle is formed with a spherical enlargement i6 supported in spherical ilanges il and i8 on the bracket end H and the end of the housing, respectively. Preferably the enlargement l@ is formed with an axial slot at one side thereof into which a tongue i9 on the separator plate I4 projects to prevent the handle from turning while permitting free angular movement thereof.

The handle is sealed in the housing Il and is urged to a centered position coaxial with the housing by a disc 2i of resilient material such as rubber. The disc 2i is supported between a ring 22 fitting in the housing and a ring 23 overlying the outer face of the disc. Preferably the ring 23 has a center opening therein formed with projecting lobes 24 in which the handle may swing so that tilting movement of the handle is limited to preselected directions. The disc 23 is angularly located in the housing by means of tabs 25 thereon to t in the slots 26 in the housing outer wall. Therefore the angular positions of the lobes 24 are accurately located properly to control tilting of the handle.

The disc 23 is held in place by an insulating sleeve 2l fitting in the housing and seated at one end against the disc 23 and having its opposite end against an insulating cover disc 28 which closes the open end of the housing. The cover disc 28 is formed in its periphery with notches to receive axially extending tabs 29 on the housing wall. To secure the cover disc in place the tabs 29 are bent over as shown in the drawings.

The cover disc 28 carries a central contact seat 3l having a flat seating surface and an upstanding peripheral flange 32. The contact seat receives the base 33 of a tiltable contact disc which has a flange 34 extending outward from the base and a concave surface 35 opposite the base and radially inward of the flange. The flange is adapted to engage xed contacts S6 carried by the cover disc 28 around the contact seat 3l. As shown, four fixed contacts 35 are provided spaced 90 around the contact seat although more or less fixed contacts could be used to control a greater number of different circuits if desired.

The contact disc is adapted to be tilted to engage fixed contacts by means of spring pressed plunger 3,? fitting slidably into the tubular handle l and urged outwardly thereof by the spring 38. At its outer end the plunger carries a cup member 3l) receiving a ball @l for universal rotation, as more particularly described and claimed in my copending application, Serial No. 303,567' led August 9, 1952. v Y

The ball il engages the concave surface, 35 of the contact disc and when the handle is in its centered position, as shown in Figure 2 holds the, base of the contact disc against the contact seat. When the handle is swung as shown in Figure 3, the disc will be tilted so that its flange 3d will engageons `or the other of the fixed contacts to complete a circuit therewith.

According to the present invention to insure that the rdisc will tilt only toward one of the fixed contacts, the contact seat is defined by a series of connected straight lines and the flange 32 isA formed bya series of connected straight sections. Where four lixed contacts are employed, as shown, the contact seat is square and the contact flange 32 is also square. The base 33, of the Contact disc, asbest seen in Figure 6, is square to fit relatively closely within the flange 32 and the flangeand the edge of the base may be curved as illustrated so that the base can roc.- easily over the flange and will contact the flange over a substantial area when the disc is tilted.

With this construction the disc will tilt easily across the straight portions of the flange so that it will be guided accurately into engagement with a selected one of the fixed contacts However, even if the handle is not swung accurately toward the Contact which is to be engaged, the innerengaging straight edge portions of the con-` tact seat and the base will still insure that the disc swings in. the desired angular direction to engage the selected fixed contact. Furthermore, it is Vsubstantially impossible with this construction for the disc to be tilted to a position in which it will engage two contacts simultaneously.

l'nA addition to guiding the tilting of the disc accurately, the straight line engagement between the contact seatrand the disc provides an elongated contact area therebetween when the disc is tilted. Therefore, the current density in the contact area will be relatively low so that heating of the contact seat and disc is minimized even under relatively heavy load conditions.

While one embodiment ofthe invention has been shown and described in detail it will be understood that that `is illustrative only and is not tobe taken as a definition of the' scope of the invention, reference being had for this pur pose to the appended claims.

What is claimedis:

l. A multiple position switch comprising a housing, acentral Contact seat carried by one end of the housing, a plurality of xed contacts carried by one end of the housing and around the contact seat, the contact seat having a substantially nat seating surface and an upstanding peripheral flange formed by a plurality ofpstraight sections registering with the fixed contacts respectively, a contact disc having a base to, seat on. the. Contact seat and whose periphery is defined by a plurality of connected straight lines corresponding to the straight flange sections, a flange on the contact disc overlying and normally spaced from the fixed contacts, and a handle extending through the other end of the housing and mounted therein for universal angular movement and engaging the contact disc to tilt it along one of said straight lines as a fulcrum on the contact seat in a direction substantially normal to said one straightr ine.`

2. A multiple position switch comprising a housing, a central contact seat carried by one end of the housing, a plurality of fixed contacts carriedby said one end of the housing and spaced around the YContact seat, the contact seat having a substantially flat seating surface and an upstanding peripheral flange formed by a plurality of straightsections registering with the fixed contacts respectively, a contact disc having a basato, seat on the contact seat and whose periphery is dened by a plurality of connected straight lines corresponding to the straight flange sections, a flange on the contact disc overlying and normally spaced from the fixed contacts, the disc having a concave dished surface opposite to the base, a handle extending through the other end of the housing and mounted therein for universal angular movement, a plunger slidably carried by the handle and engaging the concave surface of the disc, and a spring urgingthev plunger outwardly of the handle toward the disc for normally maintaining said disc, handle and plunger in axial position.

3. A multiple position switch comprising a housing, a central contact seat carried by one end of the housing having a liat seating surface and a square upstand-ing peripheral flange, four fixed contacts carried by said end of the housing spaced respectively from the sides of the square flange, a Contact disc having a square base seated on the contact seat within and substantially filling the flange, a flange on the Contact disc overlying and normally spaced from the fixed contacts, and a handle projecting through the other end of` the housing and mounted therein for universal angular movement .and engaging the contact disc to tilt it along one edge of its square base, which edge serves as a fulcrum on the contact seat, in a direction substantially normal to said one edge of the contact disc.

4. A multiple position switch comprising a housing, a central contact seat carried by one end of the housing having a flat seating surface and a square upstanding peripheral i'iange, four fixed contacts carried by said end of the housing spaced respectively from the sides of the square flange, a Contact disc having a square base seated on the contact seat within and substantially filling the flange, a flange on the contact disc overlyingy and normally spaced from the fixed contacts, the disc having a concave dished surface opposite to the base, a handle projecting through the other end of the housing and mounted therein for universal angular movement, a. plunger slidably carried by the handle and engaging the concave surface of the disc, and a spring urging the plunger outwardly of the handle toward the disc for normally maintaining said disc, handle and plunger in axial position.

5. A multiple position switch comprising a housing, a central Contact seat carried by one end of the housing, a plurality of fixed contacts carried by said one end of the housing and spaced around the contact seat, the contact seat having aV substantially flatiseatng surface, a contact disc having a base to seat on the contact seat and Whose periphery is dened by a plurality of connected straight lines registering with the xed contacts respectively, said contact seat having means for maintaining said disc in such registering relation, a flange on the contact disc overlying and normally spaced from the fixed contacts, a handle extending through the other end of the housing and mounted therein for universal angular movement, and a spring press member carried by the handle and engaging the concave dished surface of the disc for normally References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,912,624 Douglas June 6, 1933 2,469,336 Kohl May 3, 1949 

